1. Field of the Invention
This invention relates to an exercising device, more particularly to an exercising device which allows a user to perform an elliptical treading exercise that simulates stair climbing.
2. Description of the Related Art
Referring to FIG. 1, a conventional treadmill exercising device 1 is shown to include a frame 1 and a linking mechanism 2. The frame 1 has a front upright post 101, a rear bracing rod 102, a handle rod 103, and two upper transverse rods 104 and two lower transverse rods extending laterally from the front upright post 101. The linking mechanism 2 has two foot links 201 respectively and pivotably mounted on the lower transverse rods 105, two damper member 202 each mounted pivotably between a respective one of the upper transverse rods 104 and a respective one of the foot links 201, and an elastic cord 203 wound on the front upright post 101 and having two ends connected to the foot links 201, respectively, and two tread pads 204 disposed on rear ends of the foot links 201. When a user grips the handle rod 103 and treads on the tread pads 204, the foot links 201 will move pivotally about the lower transverse rod 105 to permit movement of the tread pads 204 along a constant arcuate path. Since the tread pads 204 move along a generally fixed arcuate path, the user can only training a certain muscle group of the body (such as the muscles of the lower limbs), and it is impossible for the user to use such conventional treadmill exercising device to train other muscle groups (such as the abdominal muscles).
Another conventional exercising device, such as those disclosed in U.S. Pat. Nos. 7,201,706 and 7,223,209 is an elliptical exercising machine used to simulate walking or running so as to train a user's upper and lower bodies.